Flow Troubles bigger circulator or multiple?

[Nick Kendall]

Hello I have done allot of reading and studying still am struggling with the flow in my radiant heat system. I previously had it working great in my house then I got a bigger boiler and added my garage and am thinking I need a bigger pump

I currently have 9 loops of 3/4 pex Each within 10’ of 300’ to the manifolds
A pair of 5 loop manifolds one has house lines and the other has 4 garage lines I had it started last weekend with just my 9kw boiler but I found a 15kw a friend had so I switched to that and got it started up but it had a circulation pump on the bottom side so I just left it in place and am using my original taco 07 after the expansion tank My issue seems to be that I can only get flow to register through one of my manifolds at a time and when it flows it’s max if 1-2 when previously I was able to get more, and as soon as I try to turn open both manifolds I am not registering any flow on any meters
I would think just a bigger pump but since adding the just a different boiler I lost flow pressure. Any help will be greatly appreciated thanks Nick Kendall

 

[Nick Kendall]

I do have a total of 10 90s that it must travel through between intake and return and 2 T s which i previously don’t have Previously there was only 3 90s

 

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[Fitter30]

Taco 007 pumps don't produce enough head. Heres a pump that should work but before replacing the the pumps the manifolds have y strainer I'd pull them or at least the two on the return lines because the flow is going backwards.
https://www.supplyhouse.com/Grundfo...eed-Circulator-Pump-1-6-HP-115-volt-5587000-p

 

[Nick Kendall]

Taco 007 pumps don't produce enough head. Heres a pump that should work but before replacing the the pumps the manifolds have y strainer I'd pull them or at least the two on the return lines because the flow is going backwards.
https://www.supplyhouse.com/Grundfo...eed-Circulator-Pump-1-6-HP-115-volt-5587000-p

Thank you very much for your help Can you expand on flow going backwards?

 

[Fitter30]

Top manifold right flow comes out the top of the boiler going to the manifold right after the shut off valve there's a strainer that looks like a y. Piping runs through it where the cap is there's a screen, flow runs through the center catches any dirt, water flows out. Know with reverse flow water runs from the outside of strainer to the inside and out. Flow is greater from inside to out. Notice the arrow in the link for flow.
https://www.supplyhouse.com/Bluefin-WYET075-3-4-Bronze-Wye-Strainer-Lead-Free-Threaded

 

[Nick Kendall]

Great I didn’t know there way a strainer I will pull them tomorrow.
I am not seeing which of mine is flowing backwards
Could you please point it out for me
In order to get any flow I have to almost have the adjusters maxed out and the blue ends wide open as well and still am only seeing 1 Would that be because of the extra 90’s and t s?

 

[Fitter30]

Two manifolds are supply and the two return are backwards the ones with the blue caps

 

[Nick Kendall]

Two manifolds are supply and the two return are backwards the ones with the blue caps

Ok I think I understand since the water is coming through the return manifolds traveling up the lines to the manifold vs warm going down the lines So I need to switch the two blue y strainers to be flowing correct? Thanks for your help I plan on ordering that pump after Christmas Did I understand correct that it can adjust rate itself?

 

[WorthFlorida]

I know little about these systems but please answer these questions.

One pump each, one is on the output (hot) side and another on the return side? If the bottom is the return side and since it is connected with NMC cable, the rest is MC cable, was this pump was added after the original install? Was it to help with a circulation issue?

I see a pail of dirty water and a hose, was the system purged of air after the changing out? Was the expansion tank drained and pressure checked? Lately there have been a few posts where the pressure tanks failed and weird problems seem to result.

 

[Nick Kendall]

I know little about these systems but please answer these questions.

One pump each, one is on the output (hot) side and another on the return side? If the bottom is the return side and since it is connected with NMC cable, the rest is MC cable, was this pump was added after the original install? Was it to help with a circulation issue?

I see a pail of dirty water and a hose, was the system purged of air after the changing out? Was the expansion tank drained and pressure checked? Lately there have been a few posts where the pressure tanks failed and weird problems seem to result.

I just put the boiler in and it came with the pump still on the bottom From a friend I am not running that pump. I am only running the one after the expansion tank. Is the non running pump slowing or restricting?
Yes that bucket was of the water from when I was trying to fill the system. I can get it be bubble free and build 15lbs pressure and running but I just can’t get much flow ? I took and washed all 4 strainers there was some debris but it didn’t up my flow any
I wanted to flip my cold manifold y strainers around but they have a fitted end on one side that fits onto the manifold so I can’t do that Am I loosing much to that or anything else I should try before getting a bigger pump

 

[WorthFlorida]

Remove that none working pump. Though it may seem to be no restrictions any water flowing through must turn the impeller and the motor.

 

[Nick Kendall]

Remove that none working pump. Though it may seem to be no restrictions any water flowing through must turn the impeller and the motor.

Thanks that’s exactly what I was wondering Would it be beneficial to run both pumps? I had read I didnt want one before the boiler for air issues but hadn’t removed it either

 

[WorthFlorida]

Not sure, I'm not a heating expert by any means.
https://www.supplyhouse.com/Taco-007-F5-007-Cast-Iron-Circulator-1-25-HP-1983000-p

 

[Fitter30]

Ok I think I understand since the water is coming through the return manifolds traveling up the lines to the manifold vs warm going down the lines So I need to switch the two blue y strainers to be flowing correct? Thanks for your help I plan on ordering that pump after Christmas Did I understand correct that it can adjust rate itself?

No can remove them .

 

[Nick Kendall]

No can remove them .

So it’s ok to leave the y strainers on the return side backwards but I can remove the screans? Or what did that mean

 

[Fitter30]

Remove the screens

 

[WorthFlorida]

Removing the screen will determine if they're restricting the flow.